Association of chromosome 6p multiple regions with nasopharyngeal carcinoma and gene expression changes in cancer tissue

Abstract

Nasopharyngeal carcinoma (NPC) is a malignancy that has nearly 100-fold higher in southern Chinese than in most European population. NPC clusters in families, which suggests that both geography and genetics may influence disease risk. The age group is younger than most adult cancer patients. A population study has reported that the risk of suffering from NPC is 9.31 times higher in the first-degree relatives of patient with NPC than in the first-degree relatives of spouse. The heritability is 68.08%. We employed case-control analysis to study the association of Chromosome 6p regions with nasopharyngeal carcinoma. Total 360 subjects and 360 healthy controls were included. Significant associations were found for multiple markers (most significant p= 3.36E-05, rs2076483) and genes (GABBR1, HLA-A and HCG9). Further investigation of the allele frequencies between cases and controls suggested regions of micro-deletion within GABBR1 and NEDD9. Real-time PCR using 11 pairs of NPC biopsy samples confirmed significant decrease in the cancer tissues (p=0.059 and 0.015 respectively). Our study from both genetics and functional points of view demonstrated Chromosome 6p multiple regions contribute to risk of nasopharyngeal carcinoma.